All biological cells must control the flow of salts in and out of the cell. Salts are composed of charged particles called ions. Their passage is controlled by "gating" (opening and closing) ion channels. Nerve cells use the flow of ions to produce an electric current that constitutes the nerve impulse. In recent years, many diseases have been found that result from malfunctions of these channels, making understanding of the channels, particularly gating of channels, of considerable interest in matters of health as well as in fundamental biological function. The channels themselves are composed of proteins that cross the membrane surrounding the cell. This work is based on our hypothesis that water in the channel is closely associated with the protein, and that it blocks the passage of ions when the channel is closed. There is a specific type of bond involving hydrogen and either oxygen or nitrogen, called a hydrogen bond, that is considered to be responsible for the strong association of water with the protein. Sonme hydrogen bonds are shorter and stronger than the normal, fairly weak hydrogen bonds. We have some evidence supporting the idea that these short, strong hydrogen bonds (SSHB) are responsible for gating one type of channel, found in bacteria, for which structure is known. We plan to extend the calculation to channels of the type found in animals, including humans. Furthermore, as the gating model proposed here requires the transport of protons (hydrogen ions), the calculation will be extended to proton transport. A type of quantum mechanical calculation called Density Functional Theory is to be used for both purposes. Previous calculations have shown that SSHB can switch suddenly to normal, weak, bonds, as surrounding groups shift. This would allow the channel protein to relax, opening the channel. External potential may initiate the shift too. As chains of hydrogen bonds may be involved, and an initial proton transfer step may trigger a cascade, it may be that the "gating current", a small fast current preceding the opening of the channel, is in fact a cascade of protons. This possibility will be investigated too. It is hoped that the final result of this work will be a fairly complete understanding of the gating of ion channels, and thus of the way in which the nerve impulse is propagated and controlled. In addition, it should lead to the understanding of a number of channel-related diseases.